Chelsea striker Diego Costa has been replaced in the Spain squad by Iago Aspas after suffering an injury.
Costa was pictured taking part in the latest training session in Madrid on Thursday, despite having previously struggled with a groin problem that was expected to keep him out of the World Cup qualifier against Macedonia on Saturday.
Spain have since confirmed that the 28-year-old has been forced to return to London, though they have not revealed the nature of his injury.
Celta Vigo striker Aspas has been called up as his replacement and could make his first senior appearance at the age of 29 against Macedonia or England in next week's friendly.
Head coach Julen Lopetegui admitted this week that Costa's recovery had not been progressing as they had anticipated, though he remained hopeful that the former Atletico Madrid striker could play some part in the two fixtures.
The news comes as a big blow to Chelsea, with Costa having scored nine goals in 11 Premier League games to help Antonio Conte's side climb into second place in the table.
They face a difficult run of fixtures after the international break, with a visit to Middlesbrough on November 20 followed by back-to-back games against Tottenham and Manchester City.